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Performance evaluation of a novel rotational damper for structural reinforcement steel frames subjected to lateral excitations

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Earthquake Engineering and Engineering Vibration 2014年第1期13卷 75-84页

作者： M.Sanati S.E.Khadem S.Mirzabagheri h.Sanati M.Y.Khosravieh Faculty of Mechanical Engineering Tarbiat Modares University Structural Engineering Group Faculty of Civil and Environmental EngineeringTarbiat Modares University School of Mechanical Engineering College of engineeringUniversity of Tehran

In this study,a novel rotational damper called a Rotational Friction Viscoelastic Damper(RFVD) is *** viscoelastic pads are added to the Rotational Friction Damper(RFD) in addition to the friction discs used in this conventional ***,the amount of energy dissipated by the damper increases in low excitation *** fact,the input energy to the structure is simultaneously dissipated in the form of friction and heat by frictional discs and viscoelastic *** order to compare the performance of this novel damper with the earlier types,a set of experiments were carried *** to the test results,the RFVD showed a better performance in dissipating input energy to the structure when compared to the *** seismic behavior of steel frames equipped with these dampers was also numerically evaluated based on a nonlinear time history *** numerical results verifi ed the performance of the dampers in increasing the energy dissipation and decreasing the energy input to the structural *** order to achieve the maximum dissipated energy,the dampers need to be installed in certain places called critical points in the *** appropriate approach is presented to properly fi nd these ***,the performance of the RFVDs installed at these critical points was investigated in comparison to some other confi gurations and the validity of the suggested method in increasing the energy dissipation was confi rmed.

关键词： seismic excitations rotational friction-viscoelastic damper rotational damper friction pad viscoelastic material energy dissipation

The presence and partitioning behavior of flame retardants in waste,leachate,and air particles from Norwegian waste-handling facilities

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Journal of Environmental Sciences 2017年第12期29卷 115-132页

作者： Nicolas A.O.Morin Patrik L.Andersson Sarah E.hale hans Peter h.Arp Norwegian Geotechnical Institute(NGI) P.O.Box 3930Ulleval StadionN-0806 OsloNorway Environmental and Food Laboratory of Vendee(LEA V) Department of ChemistryRond-point Georges Dural CS 8080285021 La Roche-sur-YonFrance Chemistry Department Umed UniversitySE-901 87 UmeaSweden

Flame retardants in commercial products eventually make their way into the waste *** the presence of flame retardants in Norwegian landfills, incineration facilities and recycling sorting/defragmenting facilities is investigated. These facilities handled waste electrical and electronic equipment（WEEE）, vehicles, digestate, glass, combustibles, bottom ash and fly ash. The flame retardants considered included polybrominated diphenyl ethers（∑BDE-10） as well as dechlorane plus, polybrominated biphenyls, hexabromobenzene,pentabromotoluene and pentabromoethylbenzene（collectively referred to as ∑FR-7）. Plastic,WEEE and vehicles contained the largest amount of flame retardants（∑BDE-10： 45,000–210,000 μg/kg; ∑FR-7： 300–13,000 μg/kg）. It was hypothesized leachate and air concentrations from facilities that sort/defragment WEEE and vehicles would be the highest. This was supported for total air phase concentrations（∑BDE-10： 9000–195,000 pg/m^3 WEEE/vehicle facilities, 80–900 pg/m^3 in incineration/sorting and landfill sites）, but not for water leachate concentrations（e.g., ∑BDE-10： 15–3500 ng/L in WEEE/Vehicle facilities and 1–250 ng/L in landfill sites）. Landfill leachate exhibited similar concentrations as WEEE/vehicle sorting and defragmenting facility leachate. To better account for concentrations in leachates at the different facilities, waste-water partitioning coefficients, Kwastewere measured（for the first time to our knowledge for flame retardants）. WEEE and plastic waste had elevated Kwastecompared to other wastes, likely because flame retardants are directly added to these materials. The results of this study have implications for the development of strategies to reduce exposure and environmental emissions of flame retardants in waste and recycled products through improved waste management practices.

关键词： Brominated flame retardants Waste management Environmental emissions Atmospheric emissions Partitioning Leachate

Wavelet analysis of stagnation point flow of non-Newtonian nanofluid

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Applied Mathematics and Mechanics(English Edition) 2019年第8期40卷 1211-1226页

作者： M.hAMID M.USMAN R.U.hAQ4 Z.h.KhAN Wei WANG School of Mathematical Sciences Peking UniversityBeijing 100871China BIC-ESAT College of EngineeringPeking UniversityBeijing 100871China State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Engineering SciencePeking UniversityBeijing 100871China Department of Electrical Engineering Bahria UniversityIslamabad 44000Pakistan State Key Laboratory of hydraulics and Mountain River Engineering College of Water Resource & HydropowerSichuan UniversityChengdu 610065China Key Laboratory of Advanced Reactor Engineering and Safety Ministry of Education Tsinghua UniversityBeijing 100084China

The wavelet approach is introduced to study the influence of the natural convection stagnation point flow of the Williamson fluid in the presence of thermophysical and Brownian motion effects. The thermal radiation effects are considered along a permeable stretching surface. The nonlinear problem is simulated numerically by using a novel algorithm based upon the Chebyshev wavelets. It is noticed that the velocity of the Williamson fluid increases for assisting flow cases while decreases for opposing flow cases when the unsteadiness and suction parameters increase, and the magnetic effect on the velocity increases for opposing flow cases while decreases for assisting flow cases. When the thermal radiation parameter, the Dufour number, and Williamson’s fluid parameter increase, the temperature increases for both assisting and opposing flow cases. Meanwhile, the temperature decreases when the Prandtl number increases. The concentration decreases when the Soret parameter increases, while increases when the Schmidt number increases. It is perceived that the assisting force decreases more than the opposing force. The findings endorse the credibility of the proposed algorithm, and could be extended to other nonlinear problems with complex nature.

关键词： Williamson nanofluid heat and mass transfer stagnation point flow assisting and opposing flow Chebyshev wavelet method

hydroxysafflor yellow A protects against thioacetamide-induced liver fibrosis in rats via suppressing proinflammatory/fibrogenic mediators and promoting hepatic stellate cell senescence and apoptosis

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Asian Pacific Journal of Tropical Biomedicine 2023年第8期13卷 348-358页

作者： Sayed h.Seif el-Din Olfat A.hammam Shahira M.Ezzat Samira Saleh Marwa M.Safar Walaa h.El-Maadawy Naglaa M.El-Lakkany Pharmacology Department Theodor Bilharz Research InstituteWarak El-HadarImbaba P.O.Box 30Giza 12411Egypt Pathology Department Theodor Bilharz Research InstituteWarak El-HadarImbaba P.O.Box 30Giza 12411Egypt Pharmacognosy Department Faculty of PharmacyCairo UniversityCairo 11562Egypt Pharmacognosy Department Faculty of PharmacyOctober University for Modern Sciences and ArtsGizaEgypt Pharmacology and Toxicology Department Faculty of PharmacyCairo UniversityCairo 11562Egypt Pharmacology and Biochemistry Department Faculty of PharmacyThe British University in EgyptCairoEgypt

Objective:To evaluate the effect of hydroxysafflor yellow A(hSYA)on thioacetamide-induced liver ***:Thioacetamide was administered to rats intraperitoneally in doses of 200 mg/kg twice a week for 12 ***-intoxicated rats were given silymarin(50 mg/kg)or hSYA(5 mg/kg)orally every day for 8 *** enzymes,fibrosis markers,histological changes as well as immunohistochemistry of TNF-α,IL-6,p21,α-SMA,and caspase-3 were *** effect of hSYA on hSC-T6 activation/proliferation and apoptosis was also determined in ***:hSYA decreased liver enzymes,TNF-α,IL-6,and p21 expressions,hepatic PDGF-B,TIMP-1,TGF-β1,and hydroxyproline levels,as well as fibrosis score(S2 vs.S4)compared to the thioacetamide *** also downregulatedα-SMA while increasing caspase-3 ***,at 500μg/mL,hSYA had only a slightly suppressive effect on hSC proliferation,with a 9.5%***,it significantly reduced TGF-β1,inhibitedα-SMA expression,induced caspase-3 expression,and promoted cell ***:hSYA may be a potential therapeutic agent for delaying and reversing the progression of liver *** research on hSYA at higher doses and for a longer period is warranted.

关键词： hydroxysafflor yellow A Thioacetamide hepatic stellate cells Inflammatory markers Liver fibrosis p21 α-SMA Apoptosis

Analysis of genetic relationship in mutant silkworm strains of Bom-byx mori using inter simple sequence repeat (ISSR) markers

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Journal of Genetics and Genomics 2008年第5期35卷 291-297页

作者： Dhanikachalam Velu Kangayam M. Ponnuvel Murugiah Muthulakshmi Randhir K. Sinha Syed M.h. Qadri Biotechnology Laboratory Central Sericultural Germplasm Resources Centre Hosur-635109 Tamil Nadu India

Amplified inter simple sequence repeats （ISSR） markers were used to determine genetic relationships among mutant silkworm strains of Bombyx mori. Fifteen ISSR primers containing simple sequence repeat （SSR） motifs were used in this study. A total of 113 markers were produced among 20 mutant strains, of which 73.45% were found to be polymorphic. In selected mutant genetic stocks, the average number of observed allele was （1.7080 ± 0.4567）, effective alleles （1.5194 ± 0.3950） and genetic diversity （ht）（0.2901 ± 0.0415）. The dendrogram produced using the unweighted pair group method with arithmetic means （UPGMA） and cluster analysis made using Nei＇s genetic distance resulted in the formation of one major group containing 6 groups separated 20 mutant silkworm strains. Therefore, ISSR amplification is a valuable method for determining the genetic variability among mutant silkworm strains. This efficient molecular marker would be useful for characterizing a considerable number of silkworm strains maintained at the germplasm center.

关键词： genetic diversity Bombyx mori mutant strains ISSR

Vertically aligned NiS nano-flakes derived from hydrothermally prepared Ni(Oh)2 for high performance supercapacitor

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Journal of Energy Chemistry 2018年第3期27卷 791-800页

作者： A.M.Patil A.C.Lokhande P.A.Shinde J.h.Kim C.D.Lokhande Thin Film Physics Laboratory Department of PhysicsSbivaji UniversityKolbapar 416004 MHIndia Department of Materials Science and Engineering Chonnam National University 300 Yongbong-DongPuk-GuGwangju.South Korea Centre for Interdisciplinaly Research D.Y.Patil UniversityKolhapurIndia

In present work,the vertically aligned Ni S nano-flakes composed thin film is prepared by anionic exchange process in which hydrothermally prepared Ni（Oh）2is used as a parent thin film and Na2S as a sulfide ion *** synthesis process produced fully transformed and shape-controlled nano-flakes of Ni S from nano-flowers of Ni（Oh）*** electrochemical supercapacitor properties of Ni S electrode are studied with cyclic voltammetry（CV）,galvonostatic charge discharge（GCD）and electrochemical impedance spectroscopy（EIS）*** porous surface area（85 m^2/g）of Ni S nano-flakes makes large material contribution in electrochemical reaction stretching specific capacitance（Cs）of 880 F/g at scan rate of 5 m V/s and 90%electrochemical stability up to 4000 CV cycles in 2 M KOh ***,the flexible solid-state symmetric supercapacitor device（Ni S/PVA–Li ClO4/Ni S）has been fabricated using Ni S electrodes with polyvinyl alcohol（PVA）–lithium perchlorate（Li ClO4）gel *** Ni S/PVA–Li ClO4/Ni S device exhibits specific capacitance of 56 F/g with specific energy of 14.98 Wh/kg and excellent cycling stability after 2000 *** addition,the Ni S/PVA–Li ClO4/Ni S device demonstrates illumination of red light emitting diode（LED）for 60 s,which confirms the practical applicability of Ni S/PVA–Li ClO4/Ni S device in energy storage.

关键词： Anionic exchange process Nickel sulfide Nano-flakes Supercapacitor Thin film

An effective approach for low-complexity maximum likelihood based automatic modulation classification of STBC-MIMO systems

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Frontiers of Information Technology & Electronic Engineering 2020年第3期21卷 465-476页

作者： Maqsood h.ShAh Xiao-yu DANG College of Electronic and Information Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

A low-complexity likelihood methodology is proposed for automatic modulation classification of orthogonal space-time block code(STBC)based multiple-input multiple-output(MIMO)*** exploit the zero-forcing equalization technique to modify the typical average likelihood ratio test(ALRT)*** proposed ALRT function has a low computational complexity compared to existing ALRT functions for MIMO systems *** proposed approach is analyzed for blind channel scenarios when the receiver has imperfect channel state information(CSI).Performance analysis is carried out for scenarios with different numbers of ***-STBC systems with 2×2 and 2×1 and space-time transmit diversity with a 4×4 transmit and receive antenna configuration are considered to verify the proposed *** popular modulation schemes are used as the modulation test ***-Carlo simulations are performed to evaluate the proposed methodology,using the probability of correct classification as the *** results show that the proposed approach has high classification accuracy at low signal-to-noise ratios and exhibits robust behavior against high CSI estimation error variance.

关键词： Multiple-input multiple-output Space-time block code Maximum likelihood Automatic modulation classification Zero-forcing

hydroelectrolytic and Energetic Replenisher in horses Undergoing Marcha Training

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Open Journal of Veterinary Medicine 2024年第8期14卷 203-216页

作者： José D. Ribeiro Filho Bruna M. Ribeiro Micheline O. Silva Samuel R. Alves Anaïs C. Benitez Waleska M. F. Dantas Marcel F. B. Avanza Raffaella B. C. Teixeira Pedro Ancelmo N. Ermita Laice A. Silva Rinaldo B. Viana hélio C. Manso Filho Department of Veterinary Federal University of Viosa Viosa Brazil Institute of Studies of the Wet Tropic Federal University of Southern and Southeastern Par Xinguara Brazil Department of Veterinary Clinic and Surgery Federal University of Minas Gerais Belo Horizonte Brazil Institute of Animal health and Production Federal Rural University of Amazonia Belm Brazil Zootecnics Department Federal Rural University of Pernambuco Recife Brazil

The study aimed to assess the clinical, laboratory, and blood gas analysis of horses undergoing Marcha training and the effects of voluntary ingestion of hydroelectrolytic and energy replenishers after exercise. Eight horses of both genders aged between 5 and 10 years, were included in the study. The exercise consisted of a 10-min warm-up followed by 45 min uninterrupted Marcha on a flat dirt track in the morning. After exercise, the horses received one of the following treatments: Drinking water (control group);hydroelectrolytic and energy replenisher containing sodium chloride, potassium chloride, calcium acetate, magnesium chloride, sodium citrate, dextrose, maltodextrin, and sucrose in three different concentrations (Replenishers A, B, and C). The horses were distributed across the four treatments in a 4 × 4 Latin Squares design using a Split-plot system with 48-hr intervals. Clinical and laboratory evaluations were conducted at four time points: T0 - 5 min before exercise;T1 - up to 5 min after exercise;T2 - 2 hr after starting treatment;and T4 - 4 hr after beginning treatment. Concentrations of urea, creatinine, lactate, phosphorus, and ionized calcium significantly changed after exercise. An increase in blood ph and a decrease in chloride concentrations were observed when replenishers B and C were offered after exercise. The replacements were ingested spontaneously by the animals in a volume greater than that of the control group (water). Replacement B was the most ingested by the animals, demonstrating its greatest potential.

关键词： Dehydration Electrolyte Replacement Exercise Rehydration Voluntary Intake

Stress Corrosion Cracking of X80 Pipeline Steel in Near-Neutral ph Environment under Constant Load Tests with and without Preload

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Journal of Materials Science & Technology 2011年第11期27卷 1039-1046页

作者： Y.Z. Jia J.Q. Wang E.h. han W. Ke1 State Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Department of Electromeehanical Engineering Siehuan College of Architectural Technology Deyang 318000 China

Constant load tests in NS4 solution purged with N2-5%CO2 gas mixture were conducted on American Petroleum Institute （API） X80 pipeline steel applied in the 2nd West-East （;as Pipeline project with and without preload. The results show that cracks could initiate and propagate in X80 pipeline steel in near-neutral ph environment under a constant load condition. The life of crack initiation and propagation increased with decreasing applied stress. Preload did not change its corrosion behavior obviously. however, preload reduced the time for crack initiation.

关键词： Stress corrosion cracking X80 pipeline steel Near-neutral ph solution Preload